Struct tokio::sync::RwLockReadGuard[][src]

pub struct RwLockReadGuard<'a, T: ?Sized> { /* fields omitted */ }
This is supported on crate feature sync only.
Expand description

RAII structure used to release the shared read access of a lock when dropped.

This structure is created by the read method on RwLock.

Implementations

Makes a new RwLockReadGuard for a component of the locked data.

This operation cannot fail as the RwLockReadGuard passed in already locked the data.

This is an associated function that needs to be used as RwLockReadGuard::map(...). A method would interfere with methods of the same name on the contents of the locked data.

This is an asynchronous version of RwLockReadGuard::map from the parking_lot crate.

Examples
use tokio::sync::{RwLock, RwLockReadGuard};

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
struct Foo(u32);

let lock = RwLock::new(Foo(1));

let guard = lock.read().await;
let guard = RwLockReadGuard::map(guard, |f| &f.0);

assert_eq!(1, *guard);

Attempts to make a new RwLockReadGuard for a component of the locked data. The original guard is returned if the closure returns None.

This operation cannot fail as the RwLockReadGuard passed in already locked the data.

This is an associated function that needs to be used as RwLockReadGuard::try_map(..). A method would interfere with methods of the same name on the contents of the locked data.

This is an asynchronous version of RwLockReadGuard::try_map from the parking_lot crate.

Examples
use tokio::sync::{RwLock, RwLockReadGuard};

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
struct Foo(u32);

let lock = RwLock::new(Foo(1));

let guard = lock.read().await;
let guard = RwLockReadGuard::try_map(guard, |f| Some(&f.0)).expect("should not fail");

assert_eq!(1, *guard);

Trait Implementations

Formats the value using the given formatter. Read more

The resulting type after dereferencing.

Dereferences the value.

Formats the value using the given formatter. Read more

Executes the destructor for this type. Read more

Auto Trait Implementations

Blanket Implementations

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Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

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Converts the given value to a String. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.